Manual, digital, and AI tumour-infiltrating lymphocyte scoring: a secondary analysis of the APHINITY randomised trial

In a secondary analysis of the APHINITY randomised trial in HER2-positive early breast cancer, standardised manual scoring of stromal tumour-infiltrating lymphocytes (sTILs) proved reproducible, while digital and AI-based methods delivered consistent prognostic and treatment-benefit stratification despite only modest inter-platform correlation. AI-derived spatial metrics offered complementary information beyond simple sTIL density, suggesting a path toward more scalable immune microenvironment assessment. The authors call for independent validation and further evaluation of clinical utility for stratifying contemporary HER2-directed therapies.